Abstract:
The first CD-ROM contains the Second Edition of data pertaining to the First Airborne Arctic Stratospheric Expedition (AASE-I) which was based in Stavanger, Norway during January and February, 1989. The First Edition of this dataset, produced in March 1990, was corrupted by many data errors introduced during production of the CD-ROM. The form of the errors was a random conversion of characters to ... spaces but hopefully the random data errors are not present in this edition. The second CD-ROM contains all of the 5 Hz data from the ER-2 Meteorological Measurement System (MMS) taken during the 1989 AASE-I associated with flights during which mesoscale disturbances were observed. This disc was generated as an appendix to the primary AASE-I CD-ROM dataset.

The data consists of measurements collected onboard the NASA ER-2 and DC-8 aircraft, ozonesonde soundings from three stations (Angmagssalik and Scoresbysund, Greenland, and Lerwick, U.K.), aerosol and temperature profiles from the SAM II spacecraft, global grid point values of Nimbus-7 TOMS ozone, and selected radiosonde soundings from stations in the region of the experiment. This expedition was aimed at studying the production and loss mechanisms of ozone in the north polar stratospheric environment, and the effect on ozone distribution of the Arctic polar vortex and of the cold temperatures associated with the formation of Polar Stratospheric Clouds (PSC). The mission was organized and funded by NASA, NOAA, NSF, universities, Chemical Manufacturers Association, and meteorological agencies overseas, utilizing similar instrumentation that was deployed during the Airborne Antarctic Ozone Experiment (AAOE) of 1987.

Because of its limited range, the ER-2 is not be able to survey the entire Arctic region. The ER-2 measured ozone, chlorine monoxide, nitric oxide, reactive nitrogen, nitrous oxide, total water, bromine monoxide, nitric acid, condensation nuclei, aerosol size distribution, whole air sampling, and particle chemistry and size. The DC-8 can cover a greater range, enabling it to survey the polar vortex and air processed through the cold temperature region of the polar vortex. The DC-8 collected information similar to that of the ER-2, along with the vertical distribution of ozone and aerosols, methane, and in situ measurements of ozone.

All files within this release are standard ASCII files with variable length records terminated by (ASCII decimal values 13 and 10). In general, the file naming convention uses a two character prefix to identify the measurement, followed by a six digit number giving the year, month, and day (GMT) of the flight (or balloon launch). To identify the measurement platform, a three character name as in ER2, DC8, or Bhh is used to denote the data is from the ER-2, DC-8, or balloon (hh denotes the GMT hour of launch).

AASE-I discovered that while NOx and to some degree NOy were perturbed within the arctic vortex, there was little evidence for desiccation. Under these (in contrast to the antarctic) marginally perturbed conditions, however, CLO was found to be dramatically enhanced such that a large fraction of the available (inorganic) chlorine resided in the form of CLO and its dimmer CLOOCL.